Abstract:
This research studied on health risk assessment of the workers exposed to particle-bound polycyclic aromatic hydrocarbons (PAHs) via inhalation at the worship places in Bangkok, Thailand, i.e. temple A (open area) and B (semi-open area). Particulate matters (PM2.5 and PM2.5-10) were collected on Wednesday (workday) and Sunday (weekend) for 8 hours (07.00-15.00) in summer, rainy and winter seasons in 2012. PM2.5 and PM2.5-10 were collected at three sampling sites representing working area of guard (G), janitor (J) and vendor (V) by using a personal modular impact (PMI) connected to a personal air pump (Gilian air pump). PM2.5 in ambient air (A) at each worship place was also collected by Minivol tactical air sampler (TAS). PAHs adsorbed on particles were analyzed by HPLC with fluorescence and UV detectors. The 8-hr average PM2.5 concentrations of position J at temple A were found the highest and significant greater than those of position G, V and A about 5.6, 7.1 and 9.3 fold, respectively (p<0.05). The average concentrations measured in three seasons at temple A were 509.05±243.38 µg/m3 for PM2.5 and 675.09±354.59 µg/m3 for PM10 (PM2.5 + PM2.5-10) which were significantly higher than those of PM2.5 (47.33±19.58 µg/m3) and PM10 (69.75±26.66µg/m3) at temple B (p<0.05). The number of burnt incense was significantly correlation with PM2.5 and PM10 at p< 0.01, which the Pearson correlations (or r) of PM2.5 at position A, G, J and V were 0.735, 0.791, 0.835 and 0.550, respectively. These indicate that incense burning was the predominant source of fine particles. The 8-hr average concentrations of total PAHs adsorbed on PM2.5 (t-PAHs2.5) and PM2.5-10 (t-PAHs2.5-10) in three seasons at temple A were 47.73±72.78 and 1.01±0.98 ng/m3, respectively, and those concentrations of 3.02±1.67 and 0.55±0.40 ng/m3, respectively, were found at temple B. For lifetime cancer risk (LCR) assessment of the workers at the worship places, Benzo(a)pyrene equivalent (BaPeq) was applied for the calculation and the acceptable criteria defined as the probability of cancer at the ratio of one per millions people (1x10-6). The 95% confidence intervals of LCR exposure to total BaPeq in PM2.5 (t-BaPeq2.5) and PM2.5-10 (t-BaPeq2.5-10) were in the ranges of 0.18x10-6  175.97 x10-6 and 0.007 x10-6  6.25 x10-6, respectively. When compared between different working areas, the LCR of janitor (J) at temple A showed the highest level (52.6x10-6  122.0x10-6) and higher than that of guard (G) and vender (V) about 17.7 and 16.4 fold, respectively. At temple B, only guard (G) and janitor (J) were to be potentially at risk over acceptable criteria, having the values of 1.32x10-6 and 0.15x10-6 - 1.91x10-6, respectively. Whilst the LCR of the workers exposed to t-BaPeq2.5-10 at all positions were not over the acceptable level.